* Add code to configure the following:

  * prebuffering/preroll a live stream -- this improves startup time
  * videoqmin/videoqmax/videoqdiff -- codec parameters
  * maximum bandwidth for live streams
* Add support for .ram and .rpm extensions mapping onto .rm
* Make the status page show bandwidth. Also make the .asf and .rm
  links go to .asx and .ram files.
* Make a stream only start streaming when it gets a keyframe on each
  stream. This is arguable, and it maybe ought to be restricted to
  live streams. However, since I don't think that file streams work,
  this is a step in the right direction. It improves the startup delay.
* Log an error if we are unable to delete the temp feed file.

Originally committed as revision 501 to svn://svn.ffmpeg.org/ffmpeg/trunk